[PATCH] Drop free_pages()

nr_free_pages is now a simple access to a global variable.  Make it a macro
instead of a function.

The nr_free_pages now requires vmstat.h to be included.  There is one
occurrence in power management where we need to add the include.  Directly
refrer to global_page_state() there to clarify why the #include was added.

[akpm@osdl.org: arm build fix]
[akpm@osdl.org: sparc64 build fix]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/sparc64/mm/init.c

@@ -416,7 +416,7 @@ void show_mem(void)
 	printk("Free swap:       %6ldkB\n",
 	       nr_swap_pages << (PAGE_SHIFT-10));
 	printk("%ld pages of RAM\n", num_physpages);
-	printk("%d free pages\n", nr_free_pages());
+	printk("%lu free pages\n", nr_free_pages());
 }
 
 void mmu_info(struct seq_file *m)
@@ -1593,7 +1593,7 @@ void __init mem_init(void)
 	initpages = (((unsigned long) __init_end) - ((unsigned long) __init_begin));
 	initpages = PAGE_ALIGN(initpages) >> PAGE_SHIFT;
 
-	printk("Memory: %uk available (%ldk kernel code, %ldk data, %ldk init) [%016lx,%016lx]\n",
+	printk("Memory: %luk available (%ldk kernel code, %ldk data, %ldk init) [%016lx,%016lx]\n",
 	       nr_free_pages() << (PAGE_SHIFT-10),
 	       codepages << (PAGE_SHIFT-10),
 	       datapages << (PAGE_SHIFT-10), 

include/linux/swap.h

@@ -170,11 +170,14 @@ extern void swapin_readahead(swp_entry_t, unsigned long, struct vm_area_struct *
 extern unsigned long totalram_pages;
 extern unsigned long totalreserve_pages;
 extern long nr_swap_pages;
-extern unsigned int nr_free_pages(void);
 extern unsigned int nr_free_pages_pgdat(pg_data_t *pgdat);
 extern unsigned int nr_free_buffer_pages(void);
 extern unsigned int nr_free_pagecache_pages(void);
 
+/* Definition of global_page_state not available yet */
+#define nr_free_pages() global_page_state(NR_FREE_PAGES)
+
+
 /* linux/mm/swap.c */
 extern void FASTCALL(lru_cache_add(struct page *));
 extern void FASTCALL(lru_cache_add_active(struct page *));

include/linux/vmstat.h

@@ -3,6 +3,7 @@
 
 #include <linux/types.h>
 #include <linux/percpu.h>
+#include <linux/mm.h>
 #include <linux/mmzone.h>
 #include <asm/atomic.h>
 

kernel/power/main.c

@@ -20,6 +20,7 @@
 #include <linux/cpu.h>
 #include <linux/resume-trace.h>
 #include <linux/freezer.h>
+#include <linux/vmstat.h>
 
 #include "power.h"
 
@@ -72,7 +73,8 @@ static int suspend_prepare(suspend_state_t state)
 		goto Thaw;
 	}
 
-	if ((free_pages = nr_free_pages()) < FREE_PAGE_NUMBER) {
+	if ((free_pages = global_page_state(NR_FREE_PAGES))
+			< FREE_PAGE_NUMBER) {
 		pr_debug("PM: free some memory\n");
 		shrink_all_memory(FREE_PAGE_NUMBER - free_pages);
 		if (nr_free_pages() < FREE_PAGE_NUMBER) {

mm/page_alloc.c

@@ -1440,16 +1440,6 @@ fastcall void free_pages(unsigned long addr, unsigned int order)
 
 EXPORT_SYMBOL(free_pages);
 
-/*
- * Total amount of free (allocatable) RAM:
- */
-unsigned int nr_free_pages(void)
-{
-	return global_page_state(NR_FREE_PAGES);
-}
-
-EXPORT_SYMBOL(nr_free_pages);
-
 #ifdef CONFIG_NUMA
 unsigned int nr_free_pages_pgdat(pg_data_t *pgdat)
 {